What does "compression" like?

Hi Reb.

Compression usually refers to compression of dynamics, where the softest sounds are louder and loudest lower than "normal".

How applied or not is part of how most any recording is made.

Its usually done to make all parts of the recording able to be heard more consistently, especially at lower volumes and/or when external background noise is present..

The negative for audiophiles often comes in as reducing the "jump factor" often associated with good dynamics, and also distorting the presentation of individual acoustic instruments compared to live playing.

The big negative that can come into play with dynamic range compression is when waveform peaks are clipped off as part of the process. This is the most significant and generally offensive kind of distortion often but not always introduced as part of dynamic compression.

Making recordings is an art not just nuts and bolts engineering.

Compression is one of the tools applied as part of the art and not always necessarily a bad thing. It's a tool that provides various views into the music as envisioned by recording engineers. Sometimes, that vision is a purist one, attempting to reproduce what was heard live, but that is fairly rare these days but still practiced well by those with skill who choose that style.

Rebbi,

Just as an aside, not all file compression technology is lossy.

FOr example, FLAC files can be compressed without losing any digital data, although compressed file sizes will be larger than lossy compression, like MP3, but smaller than uncompressed.

I just converted my music library from uncompressed .wav files to lossless compressed FLAC. Overall size went from ~ 900+ Gb to about 500Gb, which, based on my personal professional experience in the past developing computer image data compression algorithms, I would expect to be typical lossless compression ratios for most digital media content.